From about the thirteenth century there was introduced into the ceremony an ass, or in some cases the leader may have worn an ass’s head. We have a fifteenth century account of this version from du Tilliot, based on a document from Sens. The most startling feature was the singing during the celebration of Mass of The Song of the Ass, during which the congregation chanted “Hee-haw, hee-haw“, by way of refrain. The words of one of these songs are revealing: the song is addressed to a Satyr, who is identified with the Shepherd of the Herd, that is, the priest, and ends
“Let us clap the Satyr, to the pleasing sound of song, and to string and drums”.
According to du Tilliot, after the service the congregation danced in the choir, often throwing off their clothes. The bishops were powerless to stop these festivities, and contented themselves with attempting to moderate them. Thus a ruling of the Chapter of Sens in 1444 says that “Not more than three buckets of water are to be poured over the precentor stultorum at Vespers”, and another requests those who wish to copulate to go outside the church before doing so.
There are many features of this festival which connect it beyond doubt with the fertility religions we have been discussing. First, the occasion, which corresponds to the feast of Janus, the consort of Diana, the goddess of fertility; and the many kinds of sexual licence. Also significant are the flowers with which the clergy were in some cases wreathed. More important are the evidences of castration: not only did men put on women’s clothes but, Alcuin adds, those who did so “lost their strength”. Moreover at Sens (where we fortunately have unusually full details of the ceremony) the Vespers were sung falsetto. It is also significant that it was held on the Feast of Circumcision, since this is a vestigial form of castration. it is probably also to the point that it was in January that the worship of the Horned God took place: the connection with this branch of fertility religion is also shown by the fact that the celebrants often wore animal masks.
Ducange adds that after the ceremony the priests would parade the town in dung-carts, pelting the passers-by with ordure and singing indecent songs. (Bourke suggests that the “black pudding” which was eaten in church was in fact ordure, since boudin can mean excrement as well as black pudding.) “Fescennine jests” and the pelting of the crowd with ordure were features of the Roman fertility ceremonies.